Monday, April 13, 2015

Tonight's Sky for April 13: International Dark Sky Week Begins

Starting
tonight and running through the week, there is a little-recognized,
international event going on: International Dark Sky Week, which
serves to raise awareness about astronomers' desires to preserve the
night sky, the hazards of light pollution, and the vast amount of
money wasted on wasted energy.So,
what about Dark Sky Week?

Any
astronomer knows that there is nothing like artificial lighting,
commonly termed “light
pollution,”
to ruin a good night's observing. As an extension, after one views at
a true dark sky site, it may be hard to ever want to observe from
home again as the situation will seem utterly
depressing.
For people who are not used to looking up at the night sky, there are
still ways to notice all the light. Have you ever looked up in the
sky to see reddish-pink clouds or gone out on a night with freshly
fallen snow and found it nearly as bright as day? Well, that's
further, non-astronomical proof of light pollution.

So
why should non-astronomers care? There are many reasons.

First:
money. Believe it or not, about
50% of all outdoor lighting is wasted.
How is this done? Simple, lighting left unshielded emits light in all
directions, not just to the ground where it is intended to go. So,
for every dollar paid on an electric bill for lighting costs, 50
cents of that is spent on light that serves no purpose other than to
light the night sky.

Second:
wildlife.
Unlike humans, animals don't have clocks with which to tell time.
With the increase in artificial light, some species are getting their
days and nights mixed up, which can throw off sleep patterns and
thus, through the creation of tired animals, increase chances of
predation. Also, it is thought that some birds use the Moon and stars
for navigation. Obviously, without the starry signposts, the birds
may be getting lost. Perhaps the best known problem of light
pollution is with sea turtle babies. Which are increasingly finding
their way away from the ocean to to lighting on coastal cities.

Third
(and something everyone should care about): human
health.
Believe it or not research is starting to show that not even we human
are immune from the effect of artificial lighting. With all the extra
light, the production of melatonin, the hormone that regulates sleep,
is impacted, thus leading to sleep disorders, which can then branch
out to create other health problems. Some new research even suggests
that the artificial lighting/the interruption of natural sleep
patterns can create an increased risk for some cancers. However, it
should be known that this research has just begun and the exact
reason for the correlations is unknown.

In
short, there are many reasons for caring about light pollution, even
for non-astronomers. Between money, health, and the environment,
light pollution does much more harm than just washing-out the
beautiful night sky.